An image pickup device develops RAW data obtained by an image sensor into image data having a desired gamut, and outputs the data. The ideal gamut for image data is different depending on purposes of image data such as for example a television set, a projector, a video film, and printing. Because of this, if image data output from an image pickup device having a development function as described above is used for a purpose different from the purpose planned for the image pickup device, it is necessary to convert the gamut of the image data supplied from the image pickup device into a gamut for the different purpose.
However, in this case, it is not possible to reproduce the gamut part, which is already lacked from RAW data, of the image data output from the image pickup device. Because of this, if the image data output from the image pickup device is converted into image data having gamut wider than the gamut of the image data output from the image pickup device, color reproducibility of is decreased.
In view of this, there is known a method of transmitting RAW data obtained by an image sensor of an image pickup device to an image processing device via a medium or via communication, and developing the RAW data into image data having a desired gamut by an image processing device (e.g., see PTL 1). According to this method, the gamut and the gamma for image data may be selected at will when developing the image data. However, because RAW data is transmitted as it is via a medium or via communication, the volume of transmitted data is large, and speed enhancement is hindered.